Arc-lamp.



J. HARDER.

ARG LAMP. APPLICATION-FILED DBO. 26, 1903.

Patented July 27, 1909.

2 SHEETS-SHEET 1.

Inventor Johannes Hrdn.

b y fitty.

Witnesses:

J. HARDER.

ARG LAMP. APPLICATION FILED DEC. 26, 1903.

Patented July 27, 1909.

2 sums-sum 2.

Johannes Hrdn.

. by MA 94 W V Inventor:

other materials, the positive electrode may' which is not consumed in the normal opera-v tion of the lamp. With many of such mate- 7 fillustrated indetail I have devised means for UNITED STATES PATENT OFFICE. JOHANNESYHARDEN, OF- SGHENECTADY, NEW YOlQiTASSISNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

lino-LAMP.

. Specification of Letters Patent.

Patented July 27,1909.

Application filed December 26, 1903. Serial No. 186,632.

To all whom it may concern: I

Be it known that I, J OHANNES HARDEN, a subject of the King of Norway and Sweden, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Are-Lamps, of which the following is a lamps it has been found that where negative electrodes are used which are eomposedof some material such as the OXl(lS or carbld of titanium, the magnetic oxld of non or many be formed of some material such as copper rials which may be employed in the negative electrode to give a luminous arc the electrodetip becomes more or less non-conductive when cold due usually to the formation of a slag or film at the electrode tip. This renders it necessary, or at least desirable to provide special means for starting the are, as merely bringing the tip of the negative consuming electrode into contact with the nonconsuming positive electrode is not s'ufiiclent.

I have found that with many materials which may be employed in the negative electrode an arc can be started by causing an auxiliary .electrode of some suitable substance such as carbon or other granular good conducting material to impinge directly against the arc end of the consuming negative electrode, as a sufficiently good electrical connection is made to start aflow of current. This is particularly true if the auxiliary carbon electrode is brought into contact with the negative before the latter has had time to cool much, as I have discovered that in such cases the auxiliary electrode acts as a guard or shield which seems to lessen the resistance aequiredby the electrode tip. In the lamp which.ishereinafterdescribed and embodiment of it.

suitably actuating such an auxiliary electrode. My lamp also embodies manyother novelfeatures of construction'and arrangement not all of which are limited to use in connection with electrodes which yield a luminous arc.

The various novel features WlllOll characterize my'inventlon Wlll be pomted out wlth articularity in the claims-annexed to and orming a part of this specification. I I

For a better understanding of my invention reference may be had to the accompanying drawing in which I have illustrated one Of the drawings, Figure 1 is a side elevation of an arc lamp with the inclosing casing and globe in section Fig. 2 is a side elevation with parts in section showing a portion of the lamp mechanism viewed from the opposite side to that from which Fig. 1 is seen; ig. 3 is an end elevation showing the mechanism illustrated in Fig. 2; Fig. 4 is 0. diagram illustrating the circuits and operation of the lamp; Fig. 5 is a perspective View of a detail; and Fig. 6 is a section taken on the line 66 of Fig. 1.

' Referring to the drawing, 1 represents the main platform of the lamp, which is preferably disk-shaped. From the outer periphery of the platform 1 a pair of arms 2 extend upward, to the upper end of which a yoke 3 is pivoted. Means such as pulley 4 are carried at the upper end of the yoke 3 by which the lamp may be supported. From the-under side of the platform I a pair of parallel tubular members 5 and 6 extend downward, these members being connected at their lower ends by a cross-bar or member 7.

Intermediate the ends of members 5 and 6 a bridge member 8 is located. this member are clamped to but insulated from the members 5 and 6. The bridge member 8 is formed With a tubular portion 9 at its center. A tubular member 10 extends downward from and in line with the tubular portion 9. The tubular member 10 forms the non-consuming electrode of the lamp and is preferably formed of Wrought copper and may or may not be integral with the tubular portion 9 and the bridge S. Preferably however the member 10 is detachable and may be renewed when necessary.

The ends of is carried a cylindrical member 8 formed of sheet metal/such as copper. The purpose of this member is to aid in dissipating the heat generated in the non-consuming electrode of the lamp by the passage of current in order that the temperature of the electrode c the cross-head 11 and the left-hand end of the cross-head 12 as-viewed in Fig. 1 are I formed with yokes which partially surround the tubular membersfi and 5 respectively. The left-hand end of the cross-head 11 and the right-hand end of the cross-head 12 project into slots formed for the purpose in the tubular memlbers 5 and 6' respectively, and are rigidly secured to guide-bars or members 13 and 1.4 respectively which slide longitudinally inthe tubular members 5 and 6. The carriage 11 carries, butis insulated from, a heavy weight 15. From the under side of the weight 15 a metal rod 16 projects. The rod 16, which is carried by and extends downwardly from the weight 15, carries at its lower end a socket 17 in which a pencil 18 of carbon or the like is held. The encil 18 forms the auxiliary electrode of the amp and passes axially through the tubular members tion of acage 22.

. The lower carriage or cross-head member 12 carries'on itsupper side a socket 19/ in which the consumlng negative electrode is carried. The electrode 20 is formed of or contains some material which gives a lumi-. nous or flaming arc, such as" titanium carbid or the like. An electrical connection, comprising an insulated conductor 21 ,1 extends etween the carriage 12 and the lower por- The cage comprises a pair of annular members 23 which are concentrically placed with respect 'to the electrodes of the lamp and are connected together by vertical bars or members 24. The upper member 23 is secured to the members 5 and 6 by clamps 23 but is insulated therefrom.

A suitable electrical connection is made to the upper annular member 23 from one of the terminals of the lamps and current passes to the lower electrode through all of the vertical members 24 to the lower annular member'23. The cage 22 is arranged to surround the are between the electrodes 20 and 10 and the passage of current through the bars 24 tends to steady the arc and centralize it.

. On the upper side of the platform 1 a frame 25 is plvotally su ported by trunnions 25 which are journa ed in brackets 26- mounted on the upper side of the platform -1. This frame comprises a pair of side wheels, the journals of whichiare piyoted guides wit the plates 27 to a shaft 30 also journaled in the plates, which carries a fan 31'and a brake wheel 32. A brake-shoe 33, which 006 erates' with the brake-wheel 32, is carrie by a shaft 34 journaled in the plates 27. On the end of the shaft 34 which projects through the right-hand plate 27, asseen in Fig. 2, is secured an arm 35. A helical spring 36 having one end secured to the arm 35 and the other to a pin carried by the plate 27 normally holds the brake-shoe 33 against the brake-wheel 32 and looks it and the rest of the gearing against movement. post 37 projecting upward. from the right-hand :bracket 26 1s formed with a transverse threaded opening near its upper end through which a thumb screw 38 passes, one en which engages the lower end of the arm35 to hold the brake-shoe 33 out of engagement with the wheel 32when the frame'25 is in the osition shown in Fig. 2 and in dotted lines in Fig. 4.

A post 40 extending upwardly from the platform 1 carries near its upper end an adjustable collar 41 to which one end of the helical sprin I of the helica spring is attached to a. p1n 43 carried by the pivoted frame. The spring dof' 42 is secured. The other end 1 42 normally holds the pivoted frame in the position shown in Fig. 2 and infull lines in An arm 46 rigidly secured to the pivoted frame between tlfe side plates 27 is p votally connected at its free end to a yoke-shaped member 47 of magnetic material which conmeets a pair of magnetic cores 48 and 49 having conical ends.

Each of these cores moves axially in a pair of tubular coils 50 and 51placed oneabove the other. The coils 51 are mounted on the Within each coil 51 is mounte shell-of non-magnetic material the upper end of which enters into and forms a support for the corres onding coil 50. The she ls form lijn which'the cores 48 and 49 may slide. Portions of the 'shells are cut away latform 1 a tubular to allow movement of the yoke-shaped member 47. It will be observed that the up er ends of the core members 48 and 49 and the yoke member 47 form an armature or corefor the coils 50, while the lower end of the cores and the yoke member form an armature or core for the coils 51; Under the influence of current passing in the coils 50 the cores 48 are liftedand rock the pivoted frame in the direction indicated by the arrow in Fig; 2. The rocking movement of. the

frame is limited by the engagement of a stop 52 carried by the outer end of the frame with the up er side of the platform 1. One end of the (ill teeth of the sprocket wheel 28, through an aperture centrally'located 1n the latform' 1' and is-secured 'to the weight 15. hey other end of'the chain 53 also passes' ain- 53, which meshes with the asses A non-inductive resistance such as the coil 54 is supported on the upper side of the platform 1 as is clearly shown in Fig. 1. A post 55 extending upward from the 'latform 1 carries in its up er end a pair 0 flexible arms 56 and 57. he inner ends of the members 56 and 57 are insulated from each other. The outer ends of these members carry a couple of contact devices 58 which may consist of blocks of carbon. As is clearly shown in Fig. 1, the plate 27 carriesa pin 59 which, engaging the under surface of the outer end of the member 56, holds the contact block or device carried by it out of enlgageme nt with the contact device carried y the member 57 when the frame is in the position shown in Fig. I. When the frame is in the position shown in full lines in Fig. 4, however, the contact devices 58 are normally in contact with one another. A sliding rod 60, which has its lower end located just below member 56, passes through the )latform 1 down to and through the 0 amp which supports the cage 22, being offset at its lower end .to prevent it from falling through the latter. The lower end of this rod Wlll be struck by the cross-head 12 when it approaches the upward limit of its motion, This will move the rod to separate the contacts 58.

Referring particularly to the diagram shown in Fig. 4, one terminal 65 of the lamp is connected directly to one terminal of the coils which are in cries with each other. A conductor 66 connects the other terminal of the coils 50 to the upper annular member 23 from which a circuit exists through the bars 24 and lowerannular member 23 of the cage 22 and conductor 21 to the carriage 12 and negative electrode 20. A conductor 67 leadsfrom the other terminal 68 of the lamp to the non-consuming electrode 10. An electrical connection between the electrode 10 and the weight 15 and thereby the an);- iliary electrode 18 is indicatedin the. diagram by the conductor 69. One terminal of 5:) the coils 51, which are'in series with each other, is connected to the conductor 67 at the point 70. The other terminal of the coils 51 is connected to one terminal of the resistance conductor 54 and to the member 57 by a con- 'ductor 71. The other terminal of the resistance conductor 50 is connected to the line 66 by the conductor 72. A conductor 73 1- nects the conductor 72 with the member 56. It will be observed that when the member 56 is in such position that the contacts 58 engage one another, the members 56 and 57 and conductor 7 3 form a low resistance shunt about the resistance coil 54. It will also be.

observed that the coils 50 are in series with an are between the electrodes 10 and 20 while the coils 51 are in' shunt with the are between the electrodes 10 and 20. Assuming the ini tial out-of-servicemondition of the lamp to be that indicated in Figs. 1 and 2 in full lines and in Fig. 4 by dotted lines, it will be ob served that. the electrodes 18 and 20 are in a contact witheach other. Upon connecting the terminals 65 and 68 into a suitable circuit current will begin-to flow between the terminals starting from terminal 68, through conductors 67, electrode. 10, electrode 20, carriage 12, conductor 21, cage 22, conductor 66, coils 50 to terminal 65. Passage of cur rent through the series coils 50 will cause the cores 48 to be raised, and this will oscillate the pivoted frame in the direction indicated by the arrow in Fig. 2. As the frame 25 begins to move, the brake-shoe 33 will be moved into engagement with the brakewheel by the spring 36; This will prevent rotation of the sprocket wheel 28 relative to the frame. As is clearly shown in Figs. 2 and 4, the trunnions 25 about which the frame 25 turns are located within the periphcry of the sprocket wheel 28. As the trunsprocket wheel 28, the effect of rocking the frame 25 is to lower the electrode 20 a considerable distance and to elevate the auxiliary electrode 18 a much. smaller distance. The movement of the electrodes 18 and 20 as the frame 25 rocks is indicated in Fig. 4 by the difference between the fulland dotted line positions of the electrodes. As the electrodes 1'8 and 20 separate an arc is drawn between them. When the electrode 18 is drawn up into the tubular 'member 10, the upper end of the are ordinarily will be imme' diately transferred from the electrode 18 to the non-consuming tubular electrode 10. Upon an increase of voltage of the arc the shunt coils 51 and the spring 42 will more or less overbalance the action of the series coil 5Qrand the frame 25 will move from the fullline position shown Fig. 4 toward the dotted-line position. When the movement of the frame 25 is sufhcient to cause an engagement between the screws 38 and the arm 35 the brake-shoe33 will release the wheel 32 and the electrodes 18 and. 20 will. be moved together under the action' of the weight 15 sufficiently to allow an arc of proper length to be maintained. The fan 31 acts as a retarding device to prevent a too rapid movement of the electrode when the brake-wheel is released. i

The electrode 18 should be proportioned to consume during the feeding operation somewhat slower than the electrode 20'consumes in the regular operation of the lamp, as it is thereby certain that the electrode 18 will be long enough to operate properly. If

the electrode 18 does not consume rapidly enough so that after the feeding operation it is withdrawn within the tubularmember 10,

the arc will be maintained from it long enough to shorten it the proper amount.

The pin 59 carried by the frame 25 engages the member 56 to separate the contact blocks 58 and cut the resistance 54 into circuit with the shunt coils whenever the frame 25 moves into the position shown in the dotted lines in Fig. 4. The carriage 12 engages the rod 60 and causes it to separate the contacts, cutting the resistance into circuit whenever the electrode 20 becomes too short to be operative. The effect of cutting the resistance 50 into series with the shunt coils is to reduce the current flowing through these coils for a given potential and essen the dan ger of their destruction when the lamp gets out of order or the o erative portion of the electrode 20 is entire y consumed. This at lows the use of less expensive shunt coils, as they do not have to be constructed to sustain a voltage considerably higher than the working voltage of the coil, which would be the case in constant-potential lamps where the lamp might remam in circuit for some time after the arc had been interrupted.

As before stated, when the lamp is put out of circuit, the carbon electrode 18 moves into enga ement with the arc end of the electrode I 20. y reason of the gearing and fan 31 the 30 engagement between the electrodes 18 and 20 does not occur until a short time has elapsed after the lamp is cut out of circuit; this ives the electrode 20 time to cool slight thereby, avoiding the liability of the 35 electrodes sticking together. The period will be so short however that the end of'the pencil 18 will act as a guard or shield which will prevent in some measure the formation of a film or slag at the electrode tip which isnon-conductive when cold.

The casing 75 is secured to the latforml by means of pivotedyokes 76 w 'ch hook over lugs 77 extending upward from the platform 1. The casing 75 which extends'from a distance slightly above the bridge member 8 to the platform 1 may be formed out of sheet metal spun into any suitable form. Apertures 79, protected by a hood or guard 80, are located near-the lower end of the casing. Similar apertures 81 are formed near the upper end of the casin proper whichis surrounded by an annu ar member 82 at this point. The annular menlber 82 may be a continuation of the hood 80. Apertures 83 substantially in line with the apertures 81 are formed-in the 'u per'port on of the annular member 82. A ood84 prevents the passage of moisture orjdust through the apertures 83 and 81. Air for ventilating the lamp mechanism may enter the apertures 80 and ass out of the apertures 81 and 83'. Some 0 the arc roducts may be condensed and fall within thechamber formed between the annular member 82 and the casing proper.

A globe 85 incloses the lower portion of the lamp mechanism, being supported from the casing in any suita le manner. Spaces, through which more or less air necessary for the proper operation of the arc mayenter the globe, exist between the lower edge of the globe and a member 87 which partially closes it. The lamp mechanism located above the platform 1 may be inclosed in a suitable sheet-metal casing 88. Preferably the platform 1 is so made that it does not transmit heat readily and may embody in its construction severallayers of asbestos or the like. Provision should be made for preventing the admission of dust into the lamp mechanism located above the latform through the central aperture throug which the chain passes.

, The lamp which I have hereinbefore described and illustrated in detail is but one of the many forms in which my invention may be embodied, and it will be readily understood by those skilled in the art that many changes can be made in the form of this embodiment without departing in any manner from the spirit of my invention.

What I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an arc lamp, a non-consuming electrode, a consuming electrode formed of a material which tends to become superficially non-conducting :w'hen cooled after being heated an auxiliary electrode movable into contact with the arcing end of the consuming electrode andof such size as to cover a substantial portion of the latter, and means for causing the: auxiliary electrode to engage the consuming. electrode shortly after current is cut off from the lamp. 2; In an arc lamp, the combination of a positive non-consuming electrode, a negative consuming electrode of-such composition as to be liable to form a film or coating on its tip which is non-conducting when cold, an auxiliary electrode of powdered or granulated material, and means for making contact between the auxiliary electrode and the arcing end of the negative electrode when the lamp is cut out of circuit and before said negative electrode becomes cold, whereby the formation of a non-conducting film is prevented.

3. In an arc lamp, a frame, a wheel pivotally mounted therein, a flexible member passing over said wheel, a pair of electrodes secured one to each end of theflexible member, means for moving the frame in one direction to raise\ one electrode and lower the other electrode to bring the electrodes t0- gether, and means for moving said frame in the opposite direction to lower said one elec- .1 trode and raise the said other electrode to strike an arc, a third electrode in cooperative relation with said pair of electrodes,

said frame turning'means being arranged to vary the position of one of saidpair 'ofelectrodes more than the other of said pair with reference to the third electrode.

4. InJan arc lamp, a frame, a wheel piv-.

otally mounted therein, a flexible member passing over said wheel, a pair of electrodes secured one to each end of the flexible member, means for moving the frame in one direction to raise one electrode and lower the other electrode to bring the electrodes together, means for moving the frame to lower said one'electrod'e and raise said other elecin arranged to vary the position of one of sa1d pair of electrodes more than the other with respect (to said third electrode.

5. In an arc lamp, a main positive elecelectrode formed of carbon, and means for starting the are between the carbon electrode and the electrode containing titanium and for thereafter maintaining the are between the two main electrodes.

I 6. In an arc lam a stationary non-consuming positive e ectrode, a. cooperating consuming negative electrode, an auxiliary consuming positive electrode, and means for feeding said consuming electrodes to compensate for their consumption.

In witness whereof, I have hereunto set my hand this 7th day of December, 1903.

v J OHANNES HARDEN. Witnesses: I

JonN C.- Rown, J AMES S. ANTHONY. 

